321,614 research outputs found
Obtenção, caracterização físico química de vidros e vitro-cerâmicos baseados no sistema Li2-ZrO2-BaO-SiO2
No full textDissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas. Curso de Pós-Graduação em QuímicaNeste trabalho encontra-se descrita a preparação de vidros e vitro-cerâmicos de composição 29 % Li2O - 1% ZrO2 - x% BaO - (70 - x %) SiO2, onde x = 0, 2, 3, 5, e 6 % em mol de BaO, obtidos pelo método clássico de fusão. Os materiais foram caracterizados por Difração de Raios-X, Espectroscopia Raman, Espectroscopia no Infravermelho, Espectroscopia de Fotoelétrons Excitados por Raio-X, Microscopia Eletrônica de Varredura e Análise Térmica Diferencial. Determinaram-se o mecanismo e a cinética de cristalização dos vidros, além das propriedades físico-químicas microdureza e durabilidade química
El Tlacuache Núm. 460 (2011). 460 Año 11 (2011) marzo. El Tlacuache
No full textJuan Francisco Moncaleano: Colombia y la revolución mexicana por Ricardo Melgar Bao. -Mujeres anarquistas e imaginario femenino en el Perú a inicios del siglo XX por Perla Jaimes Navarro
Fibras de vidro a base de Li20 - Zr02 - BaO - Si02 recobertas com Nb205 para utilização em micro-extração em fase sólida
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas. Programa de Pós-graduação em QuímicaNeste trabalho são descritas as metodologias para obtenção e modificações da superfície de fibras de vidro de composição Li2O-ZrO2-BaO-SiO2. Apresenta-se também as aplicações destas fibras na determinação, por SPME, de fenol e de uma mistura de álcoois. Para obtenção das fibras de vidro construiu-se um equipamento, o qual baseia-se na técnica de estiramento. As fibras de vidro foram recobertas utilizando-se duas técnicas: Decomposição de Organometálicos, onde o etóxido de nióbio (V) foi empregado como reagente precursor do óxido de nióbio (V), e Deposição de Vapor Químico, na qual fez-se uso do cloreto de nióbio como precursor do óxido de nióbio (V).Utilizou-se da técnica de Microscopia Eletrônica de Varredura para avaliar a morfologia das fibras sem recobrimento e recobertas. O recobrimento com óxido de nióbio sobre a superfície das fibras foi estudado pela técnica de "Color Map" e as análises químicas realizadas pela Microssonda de Energia Dispersiva, ambas as técnica acopladas ao MEV. A Técnica de Micro-extração em Fase Sólida foi utilizada para avaliar a capacidade de adsorsão de compostos polares e apolares pelas fibras recobertas. Com os resultados obtidos, verficou-se que pela técnica de CVD obtem-se fibras com um recobrimento mais homogêneo e espesso. Estas fibras apresentaram melhor eficiência no processo de adsorção como verificado pelos resultados cromatográficos
CAPIRE LE CITTÀ CINESI. RI-DISEGNARE GLI STRUMENTI ITALIANI UNDERSTANDING CHINESE CITIES. REDESIGNING ITALIAN METHODS
No full textL'articolo è pubblicato sull'International Journal of Architecture, Art and Design AGATHÓN, rivista scientifica ANVUR del settore 08/D1. Scritto con BAO Li (Vice Preside della Scuola di Architettura della Southeast University di Nanchino), il saggio descrive una pluriennale attività di insegnamento (e di ricerca), basata sul tema delle "morfologie transizionali", ovvero sulle trasformazioni nel tempo della città cinese, studiate attraverso il rinnovamento di strumenti di analisi derivati dalla cultura architettonica italiana
Dataset for "Direct observation of multimode interference in rare-earth doped micro/nanofibers"
No full textData supporting the paper Bigeng Chen, Qingyang Bao and Limin Tong 'Direct observation of multimode interference in rare-earth doped micro/nanofibers' Optics Express</span
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Emergent Capabilities for Collaborative Teams in the Evolving Web Environment
No full textThis paper reports on our investigation of the latest advances for the Social Web, Web 2.0 and the Linked Data Web. These advances are discussed in terms of the latest capabilities that are available (or being made available) on the Web at the time of writing this paper. Such capabilities can be of significant benefit to teams, especially those comprised of multinational, geographically-dispersed team members. The specific context of coalition members in a rapidly formed diverse military context such as disaster relief or humanitarian aid is considered, where close working between non-government organisations and non-military teams will help to achieve results as quickly and efficiently as possible. The heterogeneity one finds in such teams, coupled with a lack of dedicated private network infrastructure, poses a number of challenges for collaboration, and the current paper represents an attempt to assess whether nascent Web-based capabilities can support such teams in terms of both their collaborative activities and their access to (and sharing of) information resources
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
2D BAO vs 3D BAO: Hints for new physics?
No full textIn the era of tensions, when precision cosmology is blooming, numerous new
theoretical models are emerging. However, it's crucial to pause and question
the extent to which the observational data we rely on are model-dependent. In
this work, we study the comoving position of the acoustic peak, a cornerstone
standard ruler in cosmology. We considered BAO observational datasets from two
distinct teams and calculated the product with the help of each BAO data
set along with SN I-a data from the Pantheon Plus sample. Our conclusion at
present is that 2D and 3D BAO datasets are compatible with each other.
Considering, no systematics in BAO, interpreting plane may
require physics beyond CDM not just while using observational BAO data
but also while observing it.Comment: 11 pages, 6 tables, 7 figures. Comments are welcome
A robust BAO extractor
No full textWe define a procedure to extract the oscillating part of a given nonlinear Power Spectrum, and derive an equation describing its evolution including the leading effects at all scales. The intermediate scales are taken into account by standard perturbation theory, the long range (IR) displacements are included by using consistency relations, and the effect of small (UV) scales is included via effective coefficients computed in simulations. We show that the UV effects are irrelevant in the evolution of the oscillating part, while they play a crucial role in reproducing the smooth component. Our "extractor" operator can be applied to simulations and real data in order to extract the Baryonic Acoustic Oscillations (BAO) without any fitting function and nuisance parameter. We conclude that the nonlinear evolution of BAO can be accurately reproduced at all scales down to z=0 by our fast analytical method, without any need of extra parameters fitted from simulations
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